The atomization of fluid into droplets is known, as are several variations of spray devices that support such functionality. Applications for such an apparatus include the spray cooling of electronic components with non-conducting fluid and use in internal combustion engines.
It is the nature of atomizers that their characteristics, including spray droplet density and the configuration of the spray cone which results, is dependent on the geometry of the spray nozzle and also the pressure and nature of the fluid delivered to the nozzle. The geometry of the spray nozzle is linked to the pressure of the fluid delivered; i.e. any given spray nozzle is only operable within a range of supply fluid pressures. When fluid is delivered within the intended range of pressures, the droplet size and distribution is optimized. The correct number of droplets, in the correct size, distributed in the correct manner, result in optimum spraying for efficient cooling.
It is therefore a problem that any spray nozzle is adapted for release of fluid at only a narrow range of rates. Where fluid is delivered at too low or too high a pressure, the droplet size and distribution are flawed, resulting in inefficient spraying.
In liquid cooling applications, it is sometimes the case that the energy output of the heat load to be cooled is less than the heat removal ability of the associated nozzle, even when the fluid pressure is reduced to the degree possible within the tolerance range. As a result, excessive fluid is used in the cooling process.
Alternatively, it may be the case that the fluid pressure delivered to a first atomizer in a common manifold or plenum cannot be lowered, due to the greater pressure requirements of a second atomizer. Consequently, the fluid is delivered to a first atomizer at excessive pressure, resulting in fluid waste.
For the foregoing reasons, there is a need for an atomizer that can be operated in a manner that allows a more precise control over the volume of fluid flow and the resulting level of heat removal. The atomizer is preferably able to remove heat loads that are smaller than that which would be removed by an atomizer of similar spray capacity operating at minimal fluid pressure consistent with the atomizer's design. The atomizer is preferably adjustable in a manner that allows selection of the overall fluid flow given any pressure. The atomizer is preferably adjustable in a manner that compensates for changing fluid pressure or changes in the level of the heat load to be removed.